1. Field of the Invention
The present invention relates to a CAD (Computer Aided Design) method and apparatus for drawing images, and in particular to a CAD tool for shaping a linear segment.
2. Description of the Related Art
CAD software allows preparation and editing of machine drawings, schematics, artwork and other images. Typically, a CAD user creates these drawings by way of use of a library of objects and a number of drawing tools that allow to create, manipulate and shape the objects.
CAD is frequently used for designing wiring patterns of a printed circuit board and other types of electronic and electrical design that requires connecting various sets of terminals for components located in different parts of the drawing with wires. CAD is also often used to create system diagrams and assembly drawings showing connections between different types of equipment using electrical cables. Wires and cables are typically represented in CAD-drawn schematics as linear segments running from one graphic representation of a component terminal to the next. It is typically desirable to bend these linear segments at right angles in order to clear various graphic representations of components and other wires. Conventionally, grid within the CAD system can be used to draw linear segments at right angles. Additionally, keyboard entry of the length and angle of a segment is used to draw segments of desired length and at desired angles.
Alternatively, an existing linear segment can be shaped to have right angles by way of snapping portions of the linear segment to grid, thereby forming right angles. Another way of drawing segments at right angles is to use a constrain angle on a segment. Typically, one side of a segment is constrained to be at a desired angle and the other side is a free moving linear segment. This method allows only one side of the segment to be properly aligned.
These conventional methods are slow and cumbersome to use. What is needed is a tool that allows shaping linear segments quickly and without the grid. The present invention satisfies this need.